Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807054165/om2176sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807054165/om2176Isup2.hkl |
CCDC reference: 672832
Key indicators
- Single-crystal X-ray study
- T = 298 K
- Mean (C-C) = 0.003 Å
- Disorder in main residue
- R factor = 0.047
- wR factor = 0.161
- Data-to-parameter ratio = 12.0
checkCIF/PLATON results
No syntax errors found
Alert level C CELLV02_ALERT_1_C The supplied cell volume s.u. differs from that calculated from the cell parameter s.u.'s by > 2 Calculated cell volume su = 11.07 Cell volume su given = 9.00 PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent ..... ? PLAT301_ALERT_3_C Main Residue Disorder ......................... 8.00 Perc. PLAT366_ALERT_2_C Short? C(sp?)-C(sp?) Bond C9 - C10 ... 1.36 Ang. PLAT366_ALERT_2_C Short? C(sp?)-C(sp?) Bond C10 - C11 ... 1.38 Ang.
Alert level G PLAT793_ALERT_1_G Check the Absolute Configuration of C1 = ... S PLAT793_ALERT_1_G Check the Absolute Configuration of C2 = ... R PLAT793_ALERT_1_G Check the Absolute Configuration of C4 = ... S PLAT793_ALERT_1_G Check the Absolute Configuration of C5 = ... R
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 5 ALERT level C = Check and explain 4 ALERT level G = General alerts; check 6 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 2 ALERT type 2 Indicator that the structure model may be wrong or deficient 1 ALERT type 3 Indicator that the structure quality may be low 0 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
The title compound was prepared by the condensation of pentan-3-one, 3-flurobenzaldehyde and ammonium acetate in 1: 2: 1 molar ratio in ethanol as reported by Noller for the similar type of Mannich bases (Noller & Baliah, 1948). Diffraction quality crystal was obtained by recrystalization of the crude sample from ethanol.
The meta fluoro part of the molecule is disordered over two positions, the disorder refining to a 0.50:0.50 ratio. Nitrogen H atoms were located in a difference Fourier map and refined isotropically. Other hydrogen atoms were fixed geometrically and allowed to ride on the parent carbon atoms,with aromatic C—H = 0.93 Å, aliphatic C—H = 0.98 Å and methyl C—H = 0.96 Å. The displacement parameters were set for phenyl and aliphatic H atoms at Uiso(H) = 1.2Ueq(C) and for methyl H atoms at 1.5Ueq(C).
Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).
Fig. 1. ORTEP of the molecule with atoms represented as 50% probability ellipsoids. Hydrogen atoms are shown as atoms of arbitrary size. | |
Fig. 2. Packing of molecules showing N—H···O interactions. |
C19H17F2NO | F(000) = 1312 |
Mr = 313.34 | Dx = 1.275 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 8210 reflections |
a = 22.2891 (4) Å | θ = 3.1–28.2° |
b = 7.0516 (1) Å | µ = 0.09 mm−1 |
c = 23.4565 (4) Å | T = 298 K |
β = 117.711 (2)° | Block, colourless |
V = 3263.89 (9) Å3 | 0.28 × 0.25 × 0.23 mm |
Z = 8 |
Bruker APEXII CCD area-detector diffractometer | 2795 independent reflections |
Radiation source: fine-focus sealed tube | 2337 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
ϕ and ω scans | θmax = 25.0°, θmin = 2.1° |
Absorption correction: multi-scan (SADABS; Bruker, 1999) | h = −25→22 |
Tmin = 0.924, Tmax = 0.983 | k = −8→8 |
18121 measured reflections | l = −27→27 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.047 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.161 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | w = 1/[σ2(Fo2) + (0.0988P)2 + 1.2426P] where P = (Fo2 + 2Fc2)/3 |
2795 reflections | (Δ/σ)max < 0.001 |
232 parameters | Δρmax = 0.26 e Å−3 |
0 restraints | Δρmin = −0.18 e Å−3 |
C19H17F2NO | V = 3263.89 (9) Å3 |
Mr = 313.34 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 22.2891 (4) Å | µ = 0.09 mm−1 |
b = 7.0516 (1) Å | T = 298 K |
c = 23.4565 (4) Å | 0.28 × 0.25 × 0.23 mm |
β = 117.711 (2)° |
Bruker APEXII CCD area-detector diffractometer | 2795 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 1999) | 2337 reflections with I > 2σ(I) |
Tmin = 0.924, Tmax = 0.983 | Rint = 0.024 |
18121 measured reflections |
R[F2 > 2σ(F2)] = 0.047 | 0 restraints |
wR(F2) = 0.161 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | Δρmax = 0.26 e Å−3 |
2795 reflections | Δρmin = −0.18 e Å−3 |
232 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
C1 | 0.10456 (8) | 0.8562 (2) | 0.14454 (8) | 0.0382 (4) | |
H1 | 0.1258 | 0.8697 | 0.1915 | 0.046* | |
C2 | 0.09171 (8) | 1.0563 (2) | 0.11377 (9) | 0.0445 (4) | |
H2 | 0.0751 | 1.0404 | 0.0674 | 0.053* | |
C3 | 0.15962 (9) | 1.1548 (2) | 0.14083 (8) | 0.0443 (4) | |
C4 | 0.21485 (9) | 1.0504 (2) | 0.13318 (9) | 0.0467 (4) | |
H4 | 0.2019 | 1.0467 | 0.0871 | 0.056* | |
C5 | 0.21931 (8) | 0.8427 (2) | 0.15674 (8) | 0.0389 (4) | |
H5 | 0.2371 | 0.8430 | 0.2036 | 0.047* | |
C6 | 0.03966 (8) | 0.7444 (2) | 0.12237 (8) | 0.0411 (4) | |
C7 | −0.00105 (10) | 0.7053 (3) | 0.05773 (9) | 0.0555 (5) | |
H7 | 0.0122 | 0.7434 | 0.0273 | 0.067* | |
C8 | −0.06142 (10) | 0.6095 (3) | 0.03868 (11) | 0.0664 (6) | |
C9 | −0.08187 (10) | 0.5475 (3) | 0.08220 (11) | 0.0624 (6) | |
H9 | −0.1224 | 0.4821 | 0.0689 | 0.075* | |
C10 | −0.04097 (10) | 0.5845 (3) | 0.14551 (11) | 0.0616 (6) | |
C11 | 0.01918 (9) | 0.6832 (2) | 0.16639 (10) | 0.0503 (5) | |
H11 | 0.0457 | 0.7082 | 0.2100 | 0.060* | |
C12 | 0.26636 (9) | 0.7275 (2) | 0.14005 (9) | 0.0435 (4) | |
C13 | 0.33343 (9) | 0.6997 (3) | 0.18524 (11) | 0.0568 (5) | |
H13 | 0.3495 | 0.7472 | 0.2268 | 0.068* | |
C14 | 0.37635 (10) | 0.6011 (3) | 0.16827 (13) | 0.0693 (6) | |
C15 | 0.35459 (12) | 0.5283 (3) | 0.10790 (14) | 0.0726 (7) | |
H15 | 0.3841 | 0.4628 | 0.0971 | 0.087* | |
C16 | 0.28812 (13) | 0.5545 (3) | 0.06381 (12) | 0.0701 (6) | |
C17 | 0.24403 (10) | 0.6536 (3) | 0.07888 (10) | 0.0563 (5) | |
H17 | 0.1992 | 0.6708 | 0.0479 | 0.068* | |
C18 | 0.03924 (10) | 1.1699 (3) | 0.12326 (12) | 0.0623 (6) | |
H18A | 0.0495 | 1.1658 | 0.1678 | 0.093* | |
H18B | −0.0049 | 1.1167 | 0.0973 | 0.093* | |
H18C | 0.0399 | 1.2991 | 0.1107 | 0.093* | |
C19 | 0.28239 (12) | 1.1518 (3) | 0.16720 (15) | 0.0802 (8) | |
H19A | 0.2761 | 1.2842 | 0.1566 | 0.120* | |
H19B | 0.3134 | 1.0988 | 0.1536 | 0.120* | |
H19C | 0.3005 | 1.1365 | 0.2129 | 0.120* | |
F1 | −0.10284 (15) | 0.5924 (5) | −0.01925 (14) | 0.1008 (10) | 0.50 |
F1A | −0.06167 (13) | 0.5306 (4) | 0.18482 (13) | 0.0796 (8) | 0.50 |
F2 | 0.43768 (15) | 0.5665 (5) | 0.21028 (18) | 0.1115 (12) | 0.50 |
F2A | 0.26635 (16) | 0.4710 (4) | 0.00831 (14) | 0.0883 (9) | 0.50 |
N1 | 0.15164 (7) | 0.75695 (18) | 0.12719 (7) | 0.0406 (4) | |
O1 | 0.16979 (7) | 1.30766 (17) | 0.16775 (8) | 0.0638 (4) | |
H1A | 0.1522 (10) | 0.630 (3) | 0.1400 (9) | 0.060 (6)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0348 (8) | 0.0340 (8) | 0.0452 (9) | 0.0019 (6) | 0.0181 (7) | 0.0023 (6) |
C2 | 0.0432 (9) | 0.0339 (9) | 0.0553 (10) | 0.0061 (7) | 0.0219 (8) | 0.0053 (7) |
C3 | 0.0528 (10) | 0.0281 (8) | 0.0564 (10) | 0.0026 (7) | 0.0291 (9) | 0.0060 (7) |
C4 | 0.0503 (10) | 0.0349 (9) | 0.0655 (11) | −0.0019 (7) | 0.0358 (9) | 0.0023 (7) |
C5 | 0.0355 (8) | 0.0350 (8) | 0.0476 (9) | 0.0001 (6) | 0.0204 (7) | 0.0024 (6) |
C6 | 0.0345 (9) | 0.0326 (8) | 0.0544 (10) | 0.0042 (6) | 0.0191 (8) | 0.0007 (7) |
C7 | 0.0506 (11) | 0.0536 (10) | 0.0556 (11) | −0.0062 (8) | 0.0189 (9) | 0.0021 (8) |
C8 | 0.0451 (11) | 0.0588 (12) | 0.0700 (14) | −0.0056 (9) | 0.0055 (10) | −0.0035 (10) |
C9 | 0.0373 (10) | 0.0522 (11) | 0.0937 (16) | −0.0067 (8) | 0.0271 (11) | −0.0111 (10) |
C10 | 0.0477 (11) | 0.0570 (11) | 0.0918 (16) | −0.0066 (9) | 0.0423 (12) | −0.0098 (10) |
C11 | 0.0445 (10) | 0.0498 (10) | 0.0611 (11) | −0.0037 (8) | 0.0284 (9) | −0.0058 (8) |
C12 | 0.0409 (9) | 0.0336 (8) | 0.0615 (11) | 0.0008 (7) | 0.0284 (8) | 0.0052 (7) |
C13 | 0.0420 (10) | 0.0563 (11) | 0.0719 (13) | 0.0046 (8) | 0.0265 (9) | 0.0074 (9) |
C14 | 0.0443 (11) | 0.0614 (12) | 0.1080 (19) | 0.0127 (9) | 0.0404 (12) | 0.0151 (12) |
C15 | 0.0716 (15) | 0.0526 (11) | 0.123 (2) | 0.0112 (10) | 0.0703 (15) | 0.0056 (12) |
C16 | 0.0767 (15) | 0.0579 (12) | 0.0961 (17) | 0.0046 (10) | 0.0574 (14) | −0.0070 (11) |
C17 | 0.0516 (11) | 0.0530 (10) | 0.0689 (13) | 0.0042 (8) | 0.0317 (10) | −0.0066 (9) |
C18 | 0.0498 (11) | 0.0421 (10) | 0.0942 (15) | 0.0109 (8) | 0.0328 (11) | 0.0025 (9) |
C19 | 0.0645 (14) | 0.0447 (11) | 0.150 (2) | −0.0121 (9) | 0.0655 (15) | −0.0101 (12) |
F1 | 0.089 (2) | 0.109 (2) | 0.0782 (19) | −0.0390 (18) | 0.0159 (16) | −0.0186 (16) |
F1A | 0.0718 (16) | 0.105 (2) | 0.0896 (17) | −0.0439 (14) | 0.0609 (14) | −0.0249 (15) |
F2 | 0.0576 (18) | 0.140 (3) | 0.132 (3) | 0.0327 (18) | 0.0401 (18) | 0.013 (2) |
F2A | 0.110 (2) | 0.0906 (19) | 0.0861 (18) | 0.0161 (16) | 0.0635 (17) | −0.0242 (15) |
N1 | 0.0372 (8) | 0.0291 (7) | 0.0569 (9) | 0.0016 (5) | 0.0231 (7) | 0.0009 (6) |
O1 | 0.0676 (9) | 0.0369 (7) | 0.0964 (11) | −0.0052 (6) | 0.0462 (8) | −0.0112 (7) |
C1—N1 | 1.468 (2) | C9—H9 | 0.9300 |
C1—C6 | 1.511 (2) | C10—F1A | 1.266 (3) |
C1—C2 | 1.550 (2) | C10—C11 | 1.382 (3) |
C1—H1 | 0.9800 | C11—H11 | 0.9300 |
C2—C3 | 1.511 (2) | C12—C17 | 1.384 (3) |
C2—C18 | 1.517 (2) | C12—C13 | 1.387 (3) |
C2—H2 | 0.9800 | C13—C14 | 1.383 (3) |
C3—O1 | 1.216 (2) | C13—H13 | 0.9300 |
C3—C4 | 1.515 (2) | C14—F2 | 1.283 (4) |
C4—C19 | 1.515 (3) | C14—C15 | 1.366 (4) |
C4—C5 | 1.552 (2) | C15—C16 | 1.369 (3) |
C4—H4 | 0.9800 | C15—H15 | 0.9300 |
C5—N1 | 1.466 (2) | C16—F2A | 1.300 (3) |
C5—C12 | 1.515 (2) | C16—C17 | 1.379 (3) |
C5—H5 | 0.9800 | C17—H17 | 0.9300 |
C6—C11 | 1.378 (3) | C18—H18A | 0.9600 |
C6—C7 | 1.385 (3) | C18—H18B | 0.9600 |
C7—C8 | 1.381 (3) | C18—H18C | 0.9600 |
C7—H7 | 0.9300 | C19—H19A | 0.9600 |
C8—F1 | 1.244 (3) | C19—H19B | 0.9600 |
C8—C9 | 1.369 (3) | C19—H19C | 0.9600 |
C9—C10 | 1.359 (3) | N1—H1A | 0.95 (2) |
N1—C1—C6 | 110.45 (13) | F1A—C10—C9 | 116.8 (2) |
N1—C1—C2 | 107.83 (13) | F1A—C10—C11 | 121.0 (2) |
C6—C1—C2 | 112.00 (13) | C9—C10—C11 | 122.1 (2) |
N1—C1—H1 | 108.8 | C6—C11—C10 | 119.79 (19) |
C6—C1—H1 | 108.8 | C6—C11—H11 | 120.1 |
C2—C1—H1 | 108.8 | C10—C11—H11 | 120.1 |
C3—C2—C18 | 112.69 (14) | C17—C12—C13 | 118.64 (17) |
C3—C2—C1 | 106.91 (13) | C17—C12—C5 | 120.78 (16) |
C18—C2—C1 | 113.61 (15) | C13—C12—C5 | 120.54 (17) |
C3—C2—H2 | 107.8 | C14—C13—C12 | 119.7 (2) |
C18—C2—H2 | 107.8 | C14—C13—H13 | 120.2 |
C1—C2—H2 | 107.8 | C12—C13—H13 | 120.2 |
O1—C3—C2 | 122.27 (15) | F2—C14—C15 | 117.5 (3) |
O1—C3—C4 | 121.79 (16) | F2—C14—C13 | 120.5 (3) |
C2—C3—C4 | 115.93 (14) | C15—C14—C13 | 121.9 (2) |
C3—C4—C19 | 111.81 (15) | C14—C15—C16 | 118.05 (19) |
C3—C4—C5 | 109.72 (13) | C14—C15—H15 | 121.0 |
C19—C4—C5 | 111.96 (16) | C16—C15—H15 | 121.0 |
C3—C4—H4 | 107.7 | F2A—C16—C15 | 117.7 (2) |
C19—C4—H4 | 107.7 | F2A—C16—C17 | 120.5 (2) |
C5—C4—H4 | 107.7 | C15—C16—C17 | 121.6 (2) |
N1—C5—C12 | 109.89 (13) | C16—C17—C12 | 120.1 (2) |
N1—C5—C4 | 109.85 (13) | C16—C17—H17 | 120.0 |
C12—C5—C4 | 110.57 (13) | C12—C17—H17 | 120.0 |
N1—C5—H5 | 108.8 | C2—C18—H18A | 109.5 |
C12—C5—H5 | 108.8 | C2—C18—H18B | 109.5 |
C4—C5—H5 | 108.8 | H18A—C18—H18B | 109.5 |
C11—C6—C7 | 118.76 (16) | C2—C18—H18C | 109.5 |
C11—C6—C1 | 120.20 (15) | H18A—C18—H18C | 109.5 |
C7—C6—C1 | 121.02 (16) | H18B—C18—H18C | 109.5 |
C8—C7—C6 | 119.69 (19) | C4—C19—H19A | 109.5 |
C8—C7—H7 | 120.2 | C4—C19—H19B | 109.5 |
C6—C7—H7 | 120.2 | H19A—C19—H19B | 109.5 |
F1—C8—C9 | 116.6 (2) | C4—C19—H19C | 109.5 |
F1—C8—C7 | 121.2 (3) | H19A—C19—H19C | 109.5 |
C9—C8—C7 | 121.8 (2) | H19B—C19—H19C | 109.5 |
C10—C9—C8 | 117.82 (18) | C5—N1—C1 | 112.54 (12) |
C10—C9—H9 | 121.1 | C5—N1—H1A | 112.6 (12) |
C8—C9—H9 | 121.1 | C1—N1—H1A | 105.6 (12) |
N1—C1—C2—C3 | −59.72 (17) | C8—C9—C10—F1A | 178.1 (2) |
C6—C1—C2—C3 | 178.56 (14) | C8—C9—C10—C11 | 0.7 (3) |
N1—C1—C2—C18 | 175.32 (15) | C7—C6—C11—C10 | 0.1 (3) |
C6—C1—C2—C18 | 53.6 (2) | C1—C6—C11—C10 | 178.65 (15) |
C18—C2—C3—O1 | 0.8 (2) | F1A—C10—C11—C6 | −178.4 (2) |
C1—C2—C3—O1 | −124.69 (18) | C9—C10—C11—C6 | −1.1 (3) |
C18—C2—C3—C4 | −179.93 (15) | N1—C5—C12—C17 | 40.4 (2) |
C1—C2—C3—C4 | 54.55 (19) | C4—C5—C12—C17 | −81.0 (2) |
O1—C3—C4—C19 | 4.6 (3) | N1—C5—C12—C13 | −141.82 (16) |
C2—C3—C4—C19 | −174.68 (17) | C4—C5—C12—C13 | 96.75 (19) |
O1—C3—C4—C5 | 129.41 (17) | C17—C12—C13—C14 | 0.5 (3) |
C2—C3—C4—C5 | −49.8 (2) | C5—C12—C13—C14 | −177.24 (17) |
C3—C4—C5—N1 | 49.75 (19) | C12—C13—C14—F2 | −176.8 (3) |
C19—C4—C5—N1 | 174.51 (16) | C12—C13—C14—C15 | −0.4 (3) |
C3—C4—C5—C12 | 171.21 (14) | F2—C14—C15—C16 | 176.1 (3) |
C19—C4—C5—C12 | −64.0 (2) | C13—C14—C15—C16 | −0.4 (3) |
N1—C1—C6—C11 | 120.53 (16) | C14—C15—C16—F2A | −174.2 (2) |
C2—C1—C6—C11 | −119.27 (16) | C14—C15—C16—C17 | 0.9 (3) |
N1—C1—C6—C7 | −61.0 (2) | F2A—C16—C17—C12 | 174.2 (2) |
C2—C1—C6—C7 | 59.2 (2) | C15—C16—C17—C12 | −0.8 (3) |
C11—C6—C7—C8 | 1.1 (3) | C13—C12—C17—C16 | 0.0 (3) |
C1—C6—C7—C8 | −177.39 (16) | C5—C12—C17—C16 | 177.81 (17) |
C6—C7—C8—F1 | 171.2 (3) | C12—C5—N1—C1 | 176.82 (12) |
C6—C7—C8—C9 | −1.5 (3) | C4—C5—N1—C1 | −61.31 (17) |
F1—C8—C9—C10 | −172.4 (3) | C6—C1—N1—C5 | −170.52 (13) |
C7—C8—C9—C10 | 0.6 (3) | C2—C1—N1—C5 | 66.81 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O1i | 0.95 (2) | 2.34 (2) | 3.2785 (18) | 169.7 (16) |
Symmetry code: (i) x, y−1, z. |
Experimental details
Crystal data | |
Chemical formula | C19H17F2NO |
Mr | 313.34 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 298 |
a, b, c (Å) | 22.2891 (4), 7.0516 (1), 23.4565 (4) |
β (°) | 117.711 (2) |
V (Å3) | 3263.89 (9) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.28 × 0.25 × 0.23 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 1999) |
Tmin, Tmax | 0.924, 0.983 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 18121, 2795, 2337 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.047, 0.161, 1.09 |
No. of reflections | 2795 |
No. of parameters | 232 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.26, −0.18 |
Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 (Farrugia, 1997).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O1i | 0.95 (2) | 2.34 (2) | 3.2785 (18) | 169.7 (16) |
Symmetry code: (i) x, y−1, z. |
Substituted piperidin-4-ones are important synthetic intermediates for the preparation of various alkaloids and pharmaceuticals (Ganellin & Spickett, 1965). Biological activities of the synthesized piperidin-4-one derivatives mainly depends on the substituents on the phenyl rings flanked either side of the secondary nitrogen. Only ortho fluoro substituted piperidin-4-one have been reported (Pham et al., 1998), which possess chair conformation.
The biological activities mainly depend on the stereochemistry (Buxton & Roberts, 1996) and the intramolecular and intermolecular hydrogen bonds with the fluorine atoms of the synthesized compound (Dunitz & Taylor, 1997; Evans & Seddon, 1997). In this study, we have incorporated the fluoro substituents at the one of the meta positions of the each phenyl groups on either side of the heterocyclic nitrogen to establish the stereochemistry and hydrogen bonding.
In the title compound C19H17F2 N O, the six membered heterocycle adopts a distorted chair conformation. The torsion angles deviate from the value of 56° expected for a perfect chair conformation (Kalsi, 1997). The equatorial dispositions of both methyl and phenyl rings which contain meta fluoro substitutents are identified by their torsion angles. The absolute configurations of the chiral atoms C1, C2, C4 and C5 are found to be R, S, R and S respectively.
According to the modified Mannich reaction reported by Noller & Baliah (1948), we expected to obtain 2,6-bis(3-fluorophenyl)piperidin-4-one by using 3-fluorobenzaldehyde, but the crystal structure reveals that the fluorine atoms occupy either side of the meta positions of each phenyl ring with a disordered site-occupancy factor of 0.5 (Fig.1).
In the crystal structure the molecules are inter linked through a strong N—H···O hydrogen bonding (Table 1, Fig.2), and also the molecules are held together by weak van der Waals interactions.